A cheat once in a while is ok. But you cheat every couple of days and your weight will go up. And a lot of people cheat.
But when they ask, and since I've lost weight they want to know--then I'll tell them. I'll also tell them that nobody loved bread and taters more than I did--and I still can only have a taste of a potato. I'm not one of those locarb eaters that can have many carbs--I'm somewhere between 40-80 a day Too many 80's--and I have to do some days of just 20.
I know people that swear they've tried, but I know they can't stop with the twinkies and pretzels. I leave desserts strictly alone--but I don't have any scrawny portions of steak or salmon, and heap up the steamed veggies and spread a real pat of butter on them.
About the only thing that can annoy me about the claims against Atkins is that we only eat bacon. The fact is, once you give up on the sugar all kinds of things start to taste very sweet--fresh vegetables and greens, for instance. But sugar-eaters are so dulled to their senses that they can't even taste what's sweet.